The present invention is directed to a method for managing wireless assets in a coverage area, and especially to managing wireless assets in a first coverage area based upon call activity in at least one second coverage area substantially adjacent with the first coverage area.
Wireless network technology is a key technology for providing mobile computing and communication capabilities. A fast growing population of users seeks a variety of mobile services, such as voice, voice over Internet Protocol (VoIP), videophone and other services. Such a growing and widespread demand for such a variety of services has made radio resource management of wireless networks a key design issue in constructing wireless networks.
Wireless communication networks, including cellular telephone networks and third generation wireless networks (e.g., Universal Mobile Telecommunications System (UMTS) and CDMA2000) require efficient wireless asset, or radio resource, management techniques for effectively employing limited bandwidth resources in high traffic environments. The management of radio resources is especially intricate and difficult in systems where users may be handed off among neighboring network controllers as they travel among various coverage areas.
Under normal traffic conditions the allocated radio resources of a network coverage area or cell can accommodate all of the demands of mobile users operating in the cell. However, during peak load periods, and especially in bursty traffic conditions, the radio resources of a cell may not be sufficient to meet all service demands that are made. Such an occurrence of a bursty demand increase is sometimes referred to as a “hot spot”. Hot spots can cause unacceptable degradation of network performance as may be manifested for example in dropped calls, fast busy signals indicating the network is busy, or similar shortcomings in communication services. Resource borrowing is one technique that may be employed to maintain acceptable service levels in hot spots or during other high traffic periods. Resource borrowing provides that wireless assets or resources, such as bandwidth, frequency or another measure of communication capacity or call handling capacity, is borrowed from a neighboring cell or call coverage area (lending call coverage area), usually an adjacent cell or call coverage area. A cell or call coverage area (borrowing call coverage area) that experiences service demands in excess of its capacity can send a borrowing request to a neighboring cell. The lending cell can permit use of certain of its capacity by the borrowing cell and in such manner the borrowing cell can gather sufficient additional resources to satisfy the increased service demand at the hot spot or other high traffic demand area.
Previous resource borrowing techniques or methods have failed to address timeliness of resource borrowing and the result has often been there is unnecessary or wasteful borrowing. Wasteful borrowing places an unnecessary burden upon lending cells. A new demand may arise in a cell, for example, when a user places a new call in the cell or when a user enters the cell from an adjacent cell in a hand off operation. When a new demand arises in a cell, once it is determined that additional resource is required to meet the new demand a resource borrowing demand process is initiated. Time is spent in such activities as contacting one or more neighboring cell as a potential lending cell, checking resources available for lending by the neighboring cells, selecting particular base stations in the neighboring cells that can lend resources, and transferring resources that are identified as available for lending from their resident base station to the base station of the borrowing cell. Often this rather lengthy multi-step process takes too long for an individual caller who made the additional service demand requiring borrowed resources and the caller hangs up, or the borrowing cell times out and drops the call. The time out aspect of service interruption is particularly likely to occur in third generation wireless networks during handoff operations because of particular real time limits imposed in those networks' operations.
There is a need for an improved method for managing wireless assets in a first coverage area or cell based upon call activity in at least one second coverage area or cell that can more efficiently effect resource borrowing to support operations in the at least one second coverage area.